What’s on the SOH-CAH-TOA poster
The rule, 4 worked examples, and the mistake everyone makes.
- In a right triangle, each trig ratio compares two specific sides, defined relative to…
- sin = O/H · cos = A/H · tan = O/A
- Have O and H, want θ = sin⁻¹(O/H)
- Have A and H, want O = use tan or sin
- θ = 30°, H = 10, find O = O = 10 sin30° = 5
- Which is adjacent? = next to θ, not the hypotenuse
- Common mistake: using the same 'opposite' for both acute angles → opposite depends on…
The hypotenuse never changes. Only opposite and adjacent depend on which angle you chose.
Questions about the SOH-CAH-TOA poster
- What’s on the SOH-CAH-TOA poster?
- The rule, 4 worked examples, and the mistake everyone makes. In a right triangle, each trig ratio compares two specific sides, defined relative to…; sin = O/H · cos = A/H · tan = O/A; Have O and H, want θ = sin⁻¹(O/H); Have A and H, want O = use tan or sin; θ = 30°, H = 10, find O = O = 10 sin30° = 5; Which is adjacent? = next to θ, not the hypotenuse; Common mistake: using the same 'opposite' for both acute angles → opposite depends on…. The hypotenuse never changes. Only opposite and adjacent depend on which angle you chose.
- Who is the SOH-CAH-TOA poster for?
- SOH-CAH-TOA is filed under 10th Grade (ages 15–16), so it matches what that year asks a child to remember. It is equally useful to an older student revisiting math, and to the parent or teacher answering the question at the kitchen table.
- When should you use the SOH-CAH-TOA poster?
- Label opposite, adjacent and hypotenuse relative to the angle FIRST. Always. A wall chart earns its place by being glanceable from where the work is happening, so SOH-CAH-TOA belongs on the wall where that math work actually happens, within glancing distance, rather than filed away.
- What other posters go with SOH-CAH-TOA?
- The Unit Circle, Sequences and Series and Circle Theorems sit alongside SOH-CAH-TOA in the 10th Grade set. Printed together they make a wall rather than a single sheet, which is how a reference set actually gets used.The Unit CircleSequences and SeriesCircle Theorems
- Is the SOH-CAH-TOA poster free to download and print?
- Yes. SOH-CAH-TOA downloads as a free PDF with no account, no email and no watermark, like everything else in the 10th Grade set. Print as many copies as you like for a home, a classroom, a library or a tutoring group; reselling the file is the only thing the licence rules out.Read the licence
- What size does the SOH-CAH-TOA poster print at?
- SOH-CAH-TOA is a vector PDF laid out for US Letter, and prints on A4 with Fit to page — the same file, no separate download. Because every mark on it is drawn rather than photographed, it stays sharp enlarged to A3, A2 or A1 at a copy shop. Colour carries emphasis only, so a greyscale print of SOH-CAH-TOA loses nothing.Printing guide
Related posters
Charts that sit alongside SOH-CAH-TOA on the same wall.
Browse every 10th Grade poster, or start from the full catalogue.